This research may be viewed as two sides of the same coin, i.e. 1) the analysis of nucleic acid structure as revealed by electron micrographs and 2) the computer synthesis of the secondary structure of nucleic acid molecules, given the sequence of bases in their known order, the synthesis being based on thermodynamic (minimum free energy) considerations. Novel methods of representing structure are being developed as well as interactive programs which allow clarification of these structures. Exploration of algorithms which will measure similarity is continuing. Both aspects would benefit from information provided by the other and one of the eventual goals is a combined analysis-synthesis procedure, which will reduce the huge combinatoric overload of secondary structure computation, which will eliminate the ambiguities of electron-micrographic images of partially denatured nucleic acid molecules.